Security and automation systems are more in use today than ever before. Improvements in communication technology make it easier to install an alarm that reports events to a central monitoring station in real-time. In particular, network technology allows alarm-reporting equipment to report events using a ubiquitous packet-based network such as the Internet. Further, with the advent of cellular technology, alarms may be reported to a central monitoring station via a standard cellular network such as a 3G network.
Given the increasing sophistication of security alarm and automation equipment and communications technology, it comes as no surprise that more information is being reported via such alarm reporting systems. For instance, not only does an alarm reporting system report the occurrence of an event, it also provides regular status updates. Further, multiple sensors may provide multiple status updates to an alarm control panel, which transmits this data constantly to a central monitoring station.
A reliable link between alarm reporting modules and central monitoring stations is vital. Alarm reporting modules that communicate using the internet may be capable of communicating with a wireless LAN (WLAN) by incorporating a wi-fi transceiver in the alarm reporting module. This provides network connectivity to a broadband modem, also on the LAN, that provides access to the internet. Some alarm reporting modules may alternatively be capable of communicating over a cellular network. A cellular transceiver communicates with a radio base station, and the base station provides access to the cellular network that is further coupled to the internet via a gateway.
However, there are inherent problems with the above methods. A WLAN is not the most reliable means for communication in all circumstances. For instance, a WLAN supporting heavy traffic may slow down or become unusable. A network node may lose power or become deactivated. In such a situation, a backup link is necessary that does not rely on the WLAN. Similarly, the local internet connection may fail in which case an alternate means for communicating with the central monitoring station is needed.
Cellular networks for transmitting data may not suffer from the setbacks described above. However, data transmission across cellular 3G networks (GPRS, CDMA, etc.) is expensive, especially when the connection is used constantly as in today's alarm reporting modules. Using an exclusively cellular transceiver would significantly increase installation, maintenance, and related costs of a security system.
Generic Access Technology (GAN) is a Fixed Mobile Convergence (FMC) technique allowing seamless roaming and handover between local and wide area networks using a dual-mode mobile phone. However, this and other existing FMC techniques have not been applied toward improving alarm reporting systems. What is needed is an alarm reporting system that maintains redundant channels of communication to the central monitoring station while minimizing costs.